Potato Salad with Shrimp and Tarragon

For the dressing

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  1/3 cup crème fraîche
  
  


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  1/3 cup mayonnaise
  
  


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  1/4 cup extra-virgin olive oil
  
  


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  3 Tbs. fresh lemon juice
  
  


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  1 Tbs. chopped fresh tarragon
  
  


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  1 tsp. kosher salt
  
  


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  1/2 tsp. freshly ground black pepper
  
  

For the salad

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  1/4 cup plain rice vinegar
  
  


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  Kosher salt
  
  


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  3-1/4 lb. baby red potatoes, scrubbed clean
  
  


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  1-1/2 cups cooked, diced shrimp
  
  


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  1-1/2 cups thinly sliced celery (include the leaves, roughly chopped)
  
  


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  1/2 cup sliced fresh chives
  
  

Make the dressing

Whisk all the dressing ingredients together in a small bowl.

Make the salad

Combine the vinegar and 2 tsp. salt in a large bowl. Let sit to dissolve the salt. Put the potatoes and 2 Tbs. salt in a 6-quart pot and add enough cold water to cover by 1 inch. Bring to a boil over high heat and reduce the heat to maintain a simmer. Cook the potatoes until barely tender when poked with a fork or skewer, 5 to 10 minutes. If the potatoes aren't all the same size, remove them as they are cooked.

Gently drain the potatoes in a colander and set aside until just cool enough to handle. Cut the potatoes into 3/4-inch chunks. Add the potatoes to the bowl with the vinegar and gently stir with a spatula to coat. With your fingers, pull apart any pieces that are stuck together.

When the potatoes have completely cooled, gently fold the shrimp, celery, and chives into the potatoes. Fold in enough dressing to generously coat the potatoes (you may not need all of the dressing). Season to taste with salt and pepper. Serve at room temperature or refrigerate until cool.